TOTAL CALCULATIONS OF OFFSETS

Norfolk Southern Train Calculations

Norfolk Southern Trains Before and After

Amount Train 1 BSFC 2 Activity Factor

20 Tier 0/unregulated 14.83 52000

10 GP33CO- ECO "mother" 17.19 45727

10 Empty "slug" 0 0

Input data 1 Average of BSFC (brake specific fuel consumption) listed in the attached Norfolk Southern contract (page 

Input data 2 Activity factor (gal/yr) assumed in Norfolk Southern Contract (page 39, among others)

Input data 3 Emission factor (EPA in its “Technical Highlights” document titled: “Emission Factors for Locomotives”. T

Input data 4 See middle chart of attached Norfolk Southern Contract for BSFC, Activity and Emission Factors for GP33

Calc. Step 1 Ten trains are converted to "slugs" which power no engine so the initial emission (10.71 tons/train-in a yea

Calc. Step 2 Ten trains are converted to "mothers" which power the cleaner GP33CO ECO trains so the emissions bene

Calc. Step 3 Sum these trains together and total savings is about 153.56 tons (107.10 tons + 46.46 tons if we conserve 

Norfolk Southern Calculation Rationale

While there have been estimates made in the past regarding emission benefits (see contract), there is unc

The 12.6 g/bhp-hr estimate is conservative since the locomotives actually are a mix of uncontrolled and Tie

Keep in mind, again, that this is fulfilled with CONSERVATIVE assumptions. One could reasonably have not 

CSX Calculations
CSX followed similar methodology as GA EPD applied for Norfolk Southern (assumed 12.4 g/bhp-hr emissio

See attached CSX contract (specifically look at pages 20-21, except 6 trains, not 5) and emissions estimate 
Tons/year Sig Figs

10 Norfolk Southern "slugs" 107.1073265

10 Norfolk Southern "mothers" 46.45453893

Total Norfolk Southern 153.5618654

CSX: 6 train replacements 35.4

Subtotal 188.9618654

Rome 8.42

Diesel Bus Program 6.42

Total Offset 203.8018654 203.8

Total Offset Required 202.35 202.35

Offset>Offset Required since total offset available is 203.8 tons and total offset needed for GA Marketing Rule Removal is 202

3 Emission Factor 4 Conversion (g to ton) Tons Emission per train in a year

12.60 1.10231E-06 10.71073

7.00 1.10231E-06 6.065279

0 N/A 0

 Norfolk Southern contract (page 39, among others)

mong others)

sion Factors for Locomotives”. The link to this information is located at: http://www.epa.gov/nonroad/locomotv/420f09025.pdf)

ty and Emission Factors for GP33CO ECO trains (the clean replacements)

mission (10.71 tons/train-in a year) is equivalent to emissions savings (10.71 tons-0 tons=10.71) per train. So 10.71 x 10 =107.1

CO trains so the emissions benefit is initial emission (10.71 tons/train-in a year) minus final emission (6.07 tons/train in a year) for a savin

ons + 46.46 tons if we conserve significant figures to two digits past the decimal)

efits (see contract), there is uncertainty regarding the exact trains to be replaced and how these trains exactly were used in the rail yards 

are a mix of uncontrolled and Tier 0 with the relevant emission factor limit for Tier 0 (overhauled before 2010 and after 2000) actually 14

 One could reasonably have not only assumed 14.0 g/bhp-hr instead of 12.6 g/bhp-hr for these old Tier 0 locomotives, but also taken into 
 (assumed 12.4 g/bhp-hr emission factor fleet average, very similar to EPD as it referenced this as a conservative estimate instead of usin

, not 5) and emissions estimate of 5.9 tons saved per year per train replacement.
eting Rule Removal is 202.35 tons so a successful demonstration.

v/420f09025.pdf)

71 x 10 =107.1

train in a year) for a savings of about 4.64 tons per "mother" (10.71 tons-6.07 tons=4.64) per train. So 4.64 x 10 = 46.4 

were used in the rail yards in Atlanta. The most appropriate conservative estimate for our purposes is to the use the rates for switchers of 

d after 2000) actually 14.0 g/bhp-hr according to 73 FR 88 25098-25352 (2008) and 63 FR 18997-19084 (1998). The use of EPA estimates 

otives, but also taken into account in the calculations that many of the original trains were uncontrolled (up to 17.4 g/bhp-hr, see "Emissio
 estimate instead of using 14.0 g/bhp), and reported 5.9 tons/locomotive per year. With 6 trains, it comes to 5.9 x 6 = 35.4 tons total. We 
64 x 10 = 46.4 

the use the rates for switchers of Tier 0, 12.6 g/bhp-hr as provided by EPA in its “Technical Highlights” document titled: “Emission Factors 

 (1998). The use of EPA estimates for emission factors are further supported by the assumption of EPA default duty cycles. In addition, sin

(up to 17.4 g/bhp-hr, see "Emission Factors for Locomotives", link: http://www.epa.gov/nonroad/locomotv/420f09025.pdf). The 12.6 g/b
es to 5.9 x 6 = 35.4 tons total. We went with this estimate.
ocument titled: “Emission Factors for Locomotives”. The link to this information is located at: http://www.epa.gov/nonroad/locomotv/42

efault duty cycles. In addition, since not sure about the exact activity of trains in the Atlanta Yard to be replaced, the average of BSFC val

motv/420f09025.pdf). The 12.6 g/bhp-hr emission factor is within the range of emission factors claimed in the Norfolk Southern contract (

ww.epa.gov/nonroad/locomotv/420f09025.pdf

replaced, the average of BSFC values provided in the NS contract (14.83 bhp-hr/gal) was used and 52000 gal/yr fuel consumption assump

n the Norfolk Southern contract (8.3-12.82 g/bhp-hr, a "range of uncertainty"), further supporting the validity of this assumption.

0 gal/yr fuel consumption assumption was applied. 

alidity of this assumption.